Parade

Ask Marilyn: Are Humans Evolving or Not?

William Lafleur of Sunderland, Vermont, writes:

Marilyn: In response to a reader's question about whether humans were still evolving, you answered, "Probably not. Our cultural practices have mostly arrested the kind of change that came from survival of the fittest." (December 12, 2012) In response to a question about bedbugs, you stated, "Living things evolve and disappear; environments are transformed. In short, nature is all about change." (January 13, 2013)

So, are humans an exception to the rule? I don't believe so. Evolution is inexorable. Our cultural practices may influence the direction and speed that evolution affects us (and other life on earth), but it does not stop the process itself. The principle driving forces behind evolution—mutation, natural selection, and genetic drift—are beyond our control. We may impact them to a small degree because we can, to some extent, modify our environment, but we cannot suppress or contain them. Marilyn responds:

Thank you for pointing this out! I shouldn't have replied so broadly about human evolution. That wasn't my intent. Evolution is undoubtedly inexorable, as you say. What I intended to convey was limited to the second sentence—that I believe the kind of change that comes from "survival of the fittest," meaning better equipped for life (not just reproductive success), is diminishing.